Improvement in lifting-jacks



PATENT QEEIcE ISAAC D. JOHNSON, OF KENNETT SQUARE, PENNSYLVANIA.

IMPROVEMENT IN LlFTlNG-JACKS.

Specification forming part of Letters Patent No. 121,721, dated December l2, 1871 antedated December 9, 1871.

To all whom it may concern:

Be it known that I, IsAAo D. JoHNsoN, M. D., of Kennett Square, in the county of Chester and State of Pennsylvania, have invented a new and Improved Mode of Raising Oarriages and Wagons; and I do hereby declare that the following is a t'ull and exact description thereof, reference being had to the accompanying drawing which makes part of this specification, and

in which- Figure 1 represents a side view of my carriagejack in its normal position 5 and Fig. 2, a similar view, showing its position when extended in raising a carriage; and Fi g. 3, a section ot' the lever H, showin the two short arms l and J.

The nature of my improvement consists in a novel device for raising' carriages and wagons when it is necessarjv to remove the wheels in the process of oiling, Src.; and- To enable others skilled in the art to make and use my improvement, I will proceed to describe its construction and operation.

The drawing represents a narrow box-frame, A, open in front except a short space at the top, which is made closed to adjust the supporting-bar C. At the lower end of the frame A is a crosspiece, B, which `serves as a base or pedestal. O represents a supporting-bar, which operates in the frameA and sustains the'weight of the wagon. At the top ofthe bar O is a cross-head, D, to receive the carriage-axles. E represents an adjust able t'ulcruin, the lower end being provided with atrunnion-pin,"1 which rests on bearings formed in the sides of the frame A. On the posterior side ofthe trunnion-pin is a projection or lug, P, which tits in grooves S S made in the sides of the bearings G Gr. B v this cont-rivance the trunnion-pin F is secured in the bearings g g, and cannot drop out when the machine is being moved about or turned lip-side down. It can easily be detached, however, b v pressing down the lever H, which will bring the upper end of the fulcrum E within the sides of the frame A, when it can be shifted at pleasure. The bearings G G are placed one above another, and form a kind of rack by which the fulcrum can be raised or lowered. H represents a lever having two short arms, I and J. standing at right angles or nearly so to the handle K. L is a socket, in which the handle K is fastened. M is a slot, with a corresponding one on the opposite side of the fraaie A, in which the adjusting-pin N glides.

I now connect the upper end ofthe fulcrum E with the short arm ot' the lever I by a hingejoint; and in like manner I connect the opposite arm J with the lower end ot' the supporting-bar O, and allow thel pin N which secures the joint to extend into the slots M and serve as a sliding adjustment to the lower end of the supporting bar O. Thus constructed it is ready for use. If, now, the lever H be pressed down, the supporting-bar C will be made to rise, and the upper end ot' the t'ulerum E carried forward and under the ends ofthe short arms ofthe levers I and J, where it will be stopped against the back ofthe frame O. In this position (Fig. 2) it will remain steadfast until the lever H is reversed, when it will be made to resume its normal position, as shown in Fig. l.

I claim as my invention and desire to secure by Letters Patentl. The trunnion-pin F with the projection or lug I on its posterior side, substantially as and for the purpose described.

2. The combination ot' the short arms of the levers I and J with the supporting-bar O and the adjustable fulcrum E, when arranged and operatingsubstantially as and for the purpose described.

ISAAC` D. JOHNSON, M. D.

Witnesses:

GEO. F. ARMSTRONG,

N. M.- GARRETT. (79) 

